Amplified widely tunable short cavity laser

Abstract

An amplified tunable source includes a short-cavity laser coupled to an optical amplifier for high power, spectrally shaped operation. The short-cavity laser is coupled to a quantum well semiconductor optical amplifier with two quantum states for broadened gain. Two preferred wavelength ranges of the amplified tunable source include 1200-1400 nm and 800-1100 nm. Also disclosed is the short cavity tunable laser coupled to a fiber amplifier. Various combinations of tunable optical filters with the amplified tunable source to reduce noise or improve spectral purity are presented.

What is claimed is: 
     
       1. An amplified tunable laser source, comprising input tunable radiation with an input power spectrum, an input center wavelength, input wavelength range and input average power, optically coupled to an input side of a semiconductor optical amplifier comprising at least one quantum well, and output tunable radiation having an output power spectrum, an output center wavelength, an output wavelength range, and output average power, emerging from an output side of said optical amplifier, wherein
 said input tunable radiation is generated by a tunable laser comprising: 
 an optical cavity including a first and second mirror; 
 a gain region interposed between said first and second mirrors; 
 a tuning region; and 
 means for adjusting an optical path length of said tuning region; 
 
       wherein:
 a free spectral range (FSR) of said optical cavity exceeds 5% of said center wavelength; 
 said tunable laser operates substantially in a single longitudinal and transverse mode over said wavelength range; 
 said means for adjusting an optical path length has a wavelength tuning frequency response with a 6-dB bandwidth greater than about 1 kHz; and 
 said optical amplifier is a resonant tunable optical amplifier tuned synchronously with said input tunable radiation. 
 
     
     
       2. The amplified tunable laser source of  claim 1 , wherein said resonant tunable optical amplifier is a vertical cavity optical amplifier. 
     
     
       3. An amplified tunable laser source, comprising input tunable radiation with an input power spectrum, an input center wavelength, input wavelength range and input average power, optically coupled to an input side of a semiconductor optical amplifier comprising at least one quantum well, and output tunable radiation having an output power spectrum, an output center wavelength, an output wavelength range, and output average power, emerging from an output side of said optical amplifier, and an optical filter between said input tunable radiation and said amplifier, to improve a side-mode suppression ratio of output tunable radiation relative to input tunable radiation; wherein
 said input tunable radiation is generated by a tunable laser comprising: 
 an optical cavity including a first and second mirror; 
 a gain region interposed between said first and second mirrors; 
 a tuning region; and 
 means for adjusting an optical path length of said tuning region; 
 
       wherein:
 a free spectral range (FSR) of said optical cavity exceeds 5% of said center wavelength; 
 said tunable laser operates substantially in a single longitudinal and transverse mode over said wavelength range; and 
 said means for adjusting an optical path length has a wavelength tuning frequency response with a 6-dB bandwidth greater than about 1 kHz. 
 
     
     
       4. An amplified tunable laser source, comprising input tunable radiation with an input power spectrum, an input center wavelength, input wavelength range and input average power, optically coupled to an input side of a semiconductor optical amplifier comprising at least one quantum well, and output tunable radiation having an output power spectrum, an output center wavelength, an output wavelength range, and output average power, emerging from an output side of said optical amplifier, wherein
 said input tunable radiation is generated by a tunable laser comprising: 
 an optical cavity including a first and second mirror; 
 a gain region interposed between said first and second mirrors; 
 a tuning region; and 
 means for adjusting an optical path length of said tuning region; 
 
       wherein:
 a free spectral range (FSR) of said optical cavity exceeds 5% of said center wavelength; 
 said tunable laser operates substantially in a single longitudinal and transverse mode over said wavelength range; 
 said means for adjusting an optical path length has a wavelength tuning frequency response with a 6-dB bandwidth greater than about 1 kHz; and 
 said optical amplifier comprises more than one amplification stage. 
 
     
     
       5. The amplified tunable laser source of  claim 4 , wherein a tunable filter is inserted between a first and second amplification stage, to suppress an ASE noise from said first stage, and said tunable filter is tuned synchronously with said input tunable radiation. 
     
     
       6. An amplified tunable laser source, comprising input tunable radiation with an input power spectrum, an input center wavelength, input wavelength range and input average power, optically coupled to an input side of a semiconductor optical amplifier comprising at least one quantum well, and output tunable radiation having an output power spectrum, an output center wavelength, an output wavelength range, and output average power, emerging from an output side of said optical amplifier, wherein
 said input tunable radiation is generated by a tunable laser comprising: 
 an optical cavity including a first and second mirror; 
 a gain region interposed between said first and second mirrors; 
 a tuning region; and 
 means for adjusting an optical path length of said tuning region; 
 
       wherein:
 a free spectral range (FSR) of said optical cavity exceeds 5% of said center wavelength; 
 said tunable laser operates substantially in a single longitudinal and transverse mode over said wavelength range; 
 said means for adjusting an optical path length has a wavelength tuning frequency response with a 6-dB bandwidth greater than about 1 kHz; and 
 a transverse mode suppression ratio of said amplified radiation exceeds that of said input tunable radiation.